Prior to my earlier inventions, as cross-referenced above, invasive procedures would be required to obtain tissue specimens from tumors, lesions or other growths located within the body but not directly exposed within a body cavity. Invasive procedures included surgical opening of the body to expose the tumor or growth, or by the use of stiff, large gauge needles, such as disclosed in U.S. Pat. Nos. 3,628,524 and 3,630,192 to Jamshidi, which allowed percutaneous entry to the desired site.
My earlier inventions have focused upon the use of needles as the means for collecting tissue samples. However, other forms of tissue collection devices have use as well. Brushes and a brushing technique have been used for many years with endoscopes for the collection of tissue specimens located directly on interior walls of the lungs. One example of a bronchial or cytology brush, manufactured by Mill-Rose Laboratories, Inc. of Mentor, Ohio is shown in FIGS. 1 and 2.
This brush is slidably retained in a hollow flexible tube and was connected to the distal end of a cable. The proximal end of the cable was connected to a handle which allowed the user to slide the brush relative to the tube so that the bristles could be moved over tissue exposed within the particular body cavity into which access could be easily reached. No seal is provided between the tube, brush, cable or handle. The distal end of the tube itself was not provided with any means for aiding the placement of the device within the body and there was no way to remove tissue from within the tube. Further, the brush was not capable of insertion into or through tissue. In fact, tissue penetration was specifically prevented by the presence of a blunt shaped member fixed to the device at the distal end of the brush.